So I have a 1971 GMC Jimmy on a 6" lift with 37's, wanting to do a gear upgrade, has stock GM 12 Bolt with 3.08 gears wanted to go to 4.56 gears. Ordered from 4WD online was originally told that a new carrier was not needed for rear axle, as we tried to install new ring and pinion found out this was not the case, called back to 4WD parts they directed me to Randy's Ring and Pinion, ordered another set and was told the same thing that a new carrier is not necessary that the Yukon gears are thicker and will make up the difference, got them here and compared them to the first set I ordered only to find out they are identical. Any assistance in this matter would be much appreciated if anyone has any parts that may help that would be much appreciated. I was trying to do this on the cheaper side since this thing will be a pavement pounder and boat hauler.